Poly[bis-(μ(2)-pyrazine-2-carboxyl-ato)-κN,O:O';κN,O:O-cadmium(II)].

In the structure of the title compound, [Cd(C(5)H(3)N(2)O(2))(2)](n), the Cd(II) ion is six-coordinated by two N atoms and four O atoms from three different pyrazine-2-carboxyl-ate ligands. One N atom and one O atom of the carboxyl-ate group in the ligand coordinate to the metal center, forming a five-membered chelate ring. The carboxyl-ate anion adopts two types of bridging modes, viz. μ(2)-O and syn-anti. Two Cd(II) ions form a centrosymmetric dimer via a μ(2)-O bridge, and the dimers are linked through the syn-anti carboxyl-ate functional group, forming a two-dimensional polymeric structure extending along (100).